Ignition switch? (part 2)

PDQ SC

Registered User
Special thanks to KMT and the-big-e for a R&R on the ignition switch. Having completed that fix I still have a problem with starting. Some times it do and sometimes it don't. I can always turn the key to on and jump to the starter at the solenoid as a means of starting. Using the switch, however, sometimes it does not turn over. Thoughts? If a connection may be the problem can anyone isolate where it may be. I plan on driving it to Ohio in a couple of weeks for some engine work and will have to cancel if I can't rely on it.
 
Check any lockout switches that may be associated with the pedal(s).

Confirm the lever on the ignition switch you just replaced is moving full range, etc. See if you can encourage a start by prodding it.

Check the major ground cables off the engine...speak up if you don't know them.
 
What lever? The ingintion switch I replaced had no moving parts. Are you refering to the key and tumbler? Based on what I am experiencing that sounds most promising. Four out of five times it will start O.K. The pedal switch does not seem to be the problem and the other connections are foreign too me. In replacing the switch I did notice that the tumbler has what appeared to be a ground wire (uncovered braid) affixed to a piece of metal that was loose (movable) on the tumbler.
 
1990 Ford Thunderbird Ignition Starter Switch


getimage.php
 
Thats what I replaced. Still trying to get the cramps out of my fingers. Wheres the lever?

The one that you connected the switch to, that goes up to the cylinder.

Try adjusting the switch a bit - if it's too far down, you'll have trouble getting the car to start. If too far up, you'll have trouble getting the ACC position to work. Off either way, and you might have trouble getting the key out.

Which reminds me .. (puts "Adjust Ig Switch" on list for tomorrow)

RwP
 
There doesn't appear to be any way to adjust it. While the forward hole is oval the back one is round and fitted. No room to slide rof or aft. What am I not understanding?
 
There doesn't appear to be any way to adjust it. While the forward hole is oval the back one is round and fitted. No room to slide for or aft. What am I not understanding?
 
Ralph, perhaps I misunderstood. You mean the piece of cast that the two screws go into that hold the switch. Where is/are the adjustment(s)?
 
What KMT suggested is this.

Next time you have trouble with the key, reach down and give the rod a shove. If that allows you to start with the key, then that is your problem. Either the part of the lock cylinder that pushes on the rod is worn, or the other end is worn or out of alignment.
 
What rod? I'm F#@^*#% dyin here. What does the rod do, look like, do you know if it has an adjustment set screw or the like? Is it truly a rod or are we still talking about the cast piece the ignition bolted onto?
 
What rod? I'm F#@^*#% dyin here. What does the rod do, look like, do you know if it has an adjustment set screw or the like? Is it truly a rod or are we still talking about the cast piece the ignition bolted onto?

Not talking about the key/cylinder/cast piece. Forget that area for now.

Take the dash apart as previously described and look down on the right side of the column, below the dash...

I'll look for another image. Send me your phone number if you like and I'll be happy to take whatever time is needed to walk you thru it...
 
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I hope kmt can help you. You have to be a bit circumspect when working on the car. Consider that you replaced a switch. Consider where the cylinder is that you put your key into. When you turn the key, consider what must happen for the turning of the key to have any influence on the switch.

It is the item that influence on the switch that you want to investigate. When the lock cylinder turns (from you turning the key) it will be pushing on a rod or a lever. This rod/lever then in turn actuates the switch to slide it through it's various positions (accessories, off, on, start).
 
Alright gentlemen. As I sit here inspecting the old "switch" I note that there is a slot on the back which exposes a notched plastic block that slides back and forth. It appears that this may be the part of the "switch" that works with the lever you refer too. Having never worked on this system before I assumed that there was circuitry in the tumbler itself interacting with the switch, but that would be, I guess, redundant. I may be able to figure it out now. Let me know if i'm on the right track and i'll get back on it when the omnipresent yardwork is conquered. Thank you in advance.
 
If this is the switch you are inspecting, then you're on the right track...at least for the moment.

getimage.php


But again, this is a five minute task to inspect and very easy to go over as long as you have a phone that works in the car of course - my dime for the call, so don't worry about me.
 
Ralph, perhaps I misunderstood. You mean the piece of cast that the two screws go into that hold the switch. Where is/are the adjustment(s)?

No, I meant the switch itself - but was thinking in general from cars I've owned and worked on.

I really don't remember, and at 100F haven't crawled under the dash to look, if the MN12's switch is adjustable or not .. If not, maybe a slight tweak of the rod (bend it a smidgen to adjust?)

Anyway - if you've replaced the switch (NOT the lock cylinder!), then most likely it's that rod - they do become distorted over time, alas.

RwP
 
My question is this?
Automatic and standard transmission

Auto, have you tried starting it in Neutral?
Standard, Is the Switch on the Clutch pedal solid attached to the Bracket for the clutch pedal?
 
Do you have Backup lights?
I wish i had pictures of the connector under the center of the dash, but access to it via remove the Center console. it's a 8-10? pin connector and if you have a test light, you can probe the Red with Blue (from ignition switch) and the White with Pink? (coming from the Neutral Safety switch on the transmission)
You do the red w/blue one and try to start the car and see if power is there then do the same with the White with pink

the wires should be easy to get too once you got the center console out thou
 
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